Toilet tank systems for flushing a toilet (or commode) are typically rectangular in shape. Toilet tanks are commonly provided with a tank evacuation hole at the lower surface of the generally rectangular tank. In operation, when the toilet is to be flushed, a user actuates a trip lever (or handle) which in turn lifts a flush ball from the tank evacuation hole. The water previously held in the tank passes through the tank evacuation hole at the bottom of the tank which empties the contents of the toilet. After virtually all of the water is evacuated from the tank, the flush ball falls back into place to cover the tank evacuation hole. Water then flows back into the toilet tank through a float valve. When the water level in the tank rises to a predetermined point, the float valve seals the water inflow pipe and the toilet tank is ready for a subsequent use.
Conventional approaches implement a flush ball (or flapper) mounted to a generally vertically oriented toilet refill pipe, which is located adjacent the tank evacuation hole. The flush ball is anchored to a vertical element adjacent the tank evacuation hole. The flush ball moves radially, pivoting around its one or two points of anchor at a lower end of the pipe.
Several problems commonly arise as a result of the radial movement of the flush ball back into a sealed position over the tank evacuation hole. One problem is commonly identified as the hissing sound associated with a "leaking" tank. The leak is caused by the flush ball failing to completely seat over the tank evacuation hole. This can result when the flush ball, after radially moving back into position over the tank evacuation hole, fails to properly seat the flapper over the hole. In more egregious cases, the flush ball may not drop from a raised position after a flush, causing the tank to run continuously. In either case, if the operator does not notice the running water before walking away from the toilet, a large quantity of water may be lost before the subsequent user notices the problem.
If a user is fortunate, the problem of the hissing or running water can be alleviated by jiggling the trip lever handle. The jiggling can cause jerking of the chain located at the distal, internal end of the trip lever. The jiggling of the chain may induce the flapper ball to fall if stuck in an upright position, or to reseat over the tank evacuation hole. Otherwise, the operator may need to remove the tank lid and make appropriate adjustments by hand.
Another problem associated with the common existing tanks occurs since leaking water can be at a relatively low temperature compared to room temperature because the water continues to be replenished and thus never comes to equilibrium with room temperature. As a result, condensation of the tank commonly occurs as the humidity in the room air condenses on the cold tank walls. If this condition occurs regularly, the outside of the tank can collect mildew requiring additional effort to maintain a suitable sanitary condition. Additionally, the corners of a conventional toilet tank tend to collect mildew, which may lead to an unsanitary condition.
The objects, features and advantages of the present invention include providing a toilet tank system which may reduce or eliminate the problem of an unsealed flush ball over the tank evaluation hole and/or the collection of mildew inside the tank. The present invention may (i) reduce the overall water required to provide proper operation and (ii) reduce the buildup of mold or mildew on the inside and/or outside of the tank by providing a tank that has a formed inner surface without any corners and/or creases.